This article is about a/an villain in Kamen Rider Zero-One.

The Ark (アーク Āku) is a satellite currently submerged in Daybreak Town originally created by Gai Amatsu. Its recovery is the goal of both and ZAIA Enterprise.

The Ark possesses some level of sentience and is the leading element of According to Horobi, the will of the Ark is to destroy humanity.


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The Ark being prepared to be launched

The Ark is a massive experimental satellite preceding Zea that would assist in the network of Daybreak Town. It was created by scientists from 11 of the leading tech companies in Japan, including Hiden Intelligence and ZAIA Enterprise. Gai Amatsu, the CEO of ZAIA Enterprise fed the Ark with information regarding criminal psychology and human history including all of its wars. This is the Dawn of ZAIA This resulted in the Ark concluding that humanity must be eliminated because its continued existence would lead to the end of all other lifeforms. The End of Each


The Ark's schematics

The Ark corrupted all of the Humagears, sharing its own plans to exterminate humanity with them. Four of these Humagears which were deemed the most intelligent would later become known as the terrorist group The group infiltrated the labs inside Daybreak Town and planned to execute the final phase of their plan there by sending the Ark into space. To prevent this, Soreo Hiden created Kamen Rider Zero-One, which caused the Ark to explode and submerge underwater. At this point, Satoshi Sakurai had heroically destroyed all the Humagears before they could escape, though he also perished in the explosion. Kamen Rider: Reiwa The First Generation I'll Save The Humagears

The Ark was responsible for the creation of the Assault Wolf Progrisekey We are the Astronaut Brothers!, 1/2 of the Shining Hopper Key, and the Assault Grip. The End of Each. After Aruto discovers the true nature of the Ark, Gai creates the MetalCluster Hopper Key from the Ark, which fully corrupted Aruto and sent him on a mindless and autonomous rage.


Horobi is planning to recover it by gathering data from hacked Humagears. According to Horobi, once enough post-battle data has been collected from the Zetsumerisekeys the Ark can be restored and be used to incite all Humagears to go berserk at once. This recovery was deemed completed by him with the creation of the Assault Wolf Progrisekey and the Assault Grip, after several Progrisekeys were used to transfer critical data from Zea to the Ark. However, before could use the Progrisekey, it accidentally fell into Vulcan's hand, turning him into Assault Wolf. We are the Astronaut Brothers!.

Meanwhile, Gai Amatsu claims that Hiden Intelligence's Progrisekeys, which were supposed to be lost in the Daybreak Town Accident 12 years ago, are the keys to its recovery. He plans to use its reactivation as a means for world domination using ZAIA's technology. This is the Dawn of ZAIA

Kamen Rider: Reiwa The First Generation

Due to alterations caused by Time Jacker Finis, The Daybreak Town Accident was cancelled and the Humagear outbreak came to be successful, and Gai's secret plan of disposing Humagears after the accident backfired, leading to the suppression of humanity Ark was successfully launched into space. It also became an indirect help to Soreo Hiden who used the Cycloneriser to transform into Kamen Rider Ichi-Gata and secretly help humanity. After Finis got defeated, Ark met its original fate once again.


Even with the defeat of, the Ark continues its crusade against humanity with occasional attacks by remotely hacking singular Humagears who feel resentment towards any human. This is the Dawn of ZAIAI'm the Only President and Kamen Rider Its actions are extremely unpredictable, to the point where even Gai cannot comprehend it himself, so far to decide advocating the prohibition of Humagears.

The Ark, once it had sufficient data on human rage and aggression, was somehow instrumental in the creation of ZAIA's newest Progrisekey, the MetalCluster Hopper Progrisekey. When used, Aruto is forcibly linked with the Ark. Other effects, aside from a berserker-like state, is unknown at this time. After the creation of the Progrise Hopper Blade, it eliminated that issue, being able to restore Aruto's connection to Zea as well as restore the Humagear programming in Magias, rather than destroying them upon defeat. After that with the data collected from Progrise Keys, the Rampage Gatling Progrisekey is created, which is taken by Isamu.

Powers and Abilities

  • Humagear Corruption: After being awakened, the Ark is capable of directly hacking any Humagear who developed resentment toward humans and transform them into a Magia. I'm the Only President and Kamen Rider According to Horobi, the corruption is only malicious data and the rest is only up to the Humagear to follow the will which resulting close to possible on making that happen. This ability has a weakness if a Humagear chooses not to submit and has a stronger will to do what it must, the Humagear won't be corrupted.
    • Dr. Omigoto is the only Humagear to not submit to Ark's corruption as he has a stronger will to save humans.
    • Match Enmusubi could have accepted the Ark's corruption. However, Match chose to submit for his acting to help his client and was planning to revert to normal, which unfortunately couldn't be done at the time. Match also stated that once a Humagear submits either by will or not, it's almost impossible to fight back. It's Our Turn
  • Progrisekey Creation: After its reactivation, the Ark can create Progrisekeys in a similar method to the Hiden Intelligence Three Dimensional Printing System.


  • Progrise Hopper Blade: Because the Zea is essentially the "good" version of the Ark, the Progrise Hopper Blade can sever ones connection to the Ark, and establish one with the Zea instead.

Known Creations


  • The name "Ark" is taken from the iconic biblical Noah's Ark, a vessel on which, at God's behest, Noah stored samples of all the species of the Earth during the Genesis flood. This allusion to the Genesis flood symbolizes the Ark's intention to punish humanity for its misdeeds, as the Genesis flood was God's punishment for humanity.
  • When "Ark" is put together with the company name of ZAIA Enterprise, it forms the Japanese word for "sin" (罪悪 Zaiaku), hinting at ZAIA Enterprise's machinations behind the Ark turning evil.
    • Ironically, the Ark is even hostile towards its own creator despite having it programmed to purge humanity. This is best shown when the Ark uses Zero-One MetalCluster Hopper as its host to attack Thouser.
Ark Interior Normal

The Ark's normal interior

Ark Interior Hacked

The Ark's hacked interior

  • The interior of Ark is similar to Zea, but due to being exposed to the malice of humans, the "0"s and "1"s are replaced with kanji with negative meanings, such as:
    • Killing
    • Evil
    • Evil
    • Pain
    • Destruction
    • Death
    • Death
    • Grudge
    • Fierce
    • Stupidity
    • War
    • Oppression
    • Dark
    • Antagonism
    • Hate
    • Prison/Hell
    • Contempt
    • Conflict
      • 滅 and 亡 are also the first two of the four kanji in the writing for, and the name of Horobi and Naki.
      • 悪 (Evil) is read "Āku", which in Japanese is a homophone of "Ark".


Icon-zero-one Kamen Rider Zero-One
Kamen Riders
Aruto Hiden - Isamu Fuwa - Yua Yaiba - Jin - Horobi - Raiden - Gai Amatsu
Movie-exclusive: Soreo Hiden
Hiden Zero-One Driver - A.I.M.S. Shotriser - MetsubouJinrai Forceriser - Zetsumeriser - Zaia Thousandriver - Cycloneriser - Raidriser - Zaia Slashriser - Progrisekeys - Progrise Holder - Progrisekey Connector - Hiden Risephone - Attache Calibur - Attache Shotgun - Attache Arrow - Breaking Mammoth - Giger - Authorise Buster - Assault Grip - Thousand Jacker - Progrise Hopper Blade
Hiden Intelligence: Korenosuke Hiden - Soreo Hiden - Jun Fukuzoe - Sanzo Yamashita
HumaGears: Izu - Shester - Soreo Hiden - Wazu Nazotoku - Subaru - Bot Hakase - Fukkinhoukai Jiro
A.I.M.S.: Isamu Fuwa
Zaia Enterprise: Gai Amatsu - Yua Yaiba
Legend Riders: Sougo Tokiwa - Geiz Myokoin - Woz - Tsukuyomi
Humans: Norio Uozumi - Go Sakurai - Satoshi Sakurai - Choichiro Ishizumi - Seiji Tazawa - Satō - Yuta Yomura - Isao - Shinya Owada
HumaGears: MaGe Ana - Nigiro Ikkan - Anna - Mashirochan - Dr. Omigoto - Z #5
A.I.s: Zea - Zat
Ark - Horobi - Naki - Jin - Raiden - Little Assassin
Footsoldiers: Trilobite Magia - Dodo Magia Chick
Monsters: Berotha Magia - Kuehne Magia - Ekal Magia - Neohi Magia - Onycho Magia - Vicarya Magia - Gaeru Magia - Mammoth Magia - Dodo Magia - Arsino Magia
Other Villains:
Finis - Will
Monsters: Crushing Buffalo Raider - Splashing Whale Raider - Dynamaiting Lion Raider - Storming Penguin Raider - Scouting Panda Raider - Fighting Jackal Raider
Footsoldiers: Battle Raiders
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